Polymer industries, biodegradable polymers

Halley P. J. Thermoplastic starch polymers, in Biodegradable polymers for industrial applications R.Smith (ed), Woodhead Pub., London, UK 2005. 

The great majority of industrial biodegradable polymers and plastics developed in recent decades are polyesters. Not all polyesters are biodegradable the biodegradation rate is influenced by the percentage and distribution of aromatic monomers in the polymer chain [23]. For this reason aliphatic-aromatic copolyesters, that combine biodegradability with enhanced mechanical properties, have been developed. 

E. A. Dawes, Novel Biodegradable Microbial Poljmers, Proceedings of an Advanced Workshop on Neiv Biosjnthetic Biodegradable Polymers of Industrial Interest, Sitges, Spain, 1990, NATO ASI Series E Apphed Science, Vol. 186, Kluwer Academic Pubhshing, London, 1990. 

In Industrial Chemicals. Recendy, as some amino acids (eg, L-glutamic acid, L-lysine, glycine, DL-alanine, DL-methionine) have become less expensive chemical materials, they have been employed in various appHcation fields. Poly(amino acid)s are attracting attention as biodegradable polymers in connection with environmental protection (236). 

Smith, R. (2005)Biodegradable Polymer for Industrial Applications, CRC Press, New York. 

Biodegradable plastics have been used on an industrial scale since the end of the 1990s when BASF launched Ecoflex . This is a fossil-based, man-made polyester but yet is completely biodegradable due to its chemical structure. This structure is also the reason why Ecoflex combines excellent mechanical properties with the good processability of synthetic thermoplastics. Ecoflex is the preferred blend partner for bio-based and biodegradable polymers, which typically do not exhibit good mechanics and processability for film applications by themselves. Ecoflex therefore is a synthetic polymer that enables the extensive use of renewable raw materials (e.g., starch). 

Chemical Industries are represented by BASF SE, Showa Denko, WACKER and DOW Chemicals, who are best qualified to present challenges and requirements of biodegradable polymers on an industrial scale. Information on mineral oil-based polyesters, poly(vinylalcohol), poly(butylenesuccinate), and new developments in the field of poly(urethanes) from renewable sources can be found within this volume. 

Middleton JC, Tipton AJ, Synthetic Biodegradable Polymers as Medical Devices, Medical Device and Diagnosis Industry, Los Angeles, CA A Canon Communications LLC, 1998,... 

In the current industrial process, nisin is manufactured by fermentation of L. lactis subsp. lactis in a milk-based medium. Biosynthesis of nisin is coupled with the growth of lactic acid bacteria and the production of a significant amount of lactic acid (7). Lactic acid is an important chemical for food processing. It can also be used as a raw material in the production of the biodegradable polymer poly(lactic) acid (12). Unfortunately, lactic acid is not recovered in the current nisin process. 

Particle design is presently a major development of supercritical fluids applications, mainly in the paint, cosmetic, pharmaceutical, and specialty chemical industries [4CM-2]. The particle formation of functional pigments with biodegradable polymer has been successfully performed by gas-saturated solution (GSS) process using scC02 and PEG in a thermostatted stirred vessel [43]. The average diameter of the particles obtained by GSS at different conditions (40 and 50 °C, 10-30 MPa) is about 0.78-1.472 pm. 

Another example where metabolic pathway engineering has made a dramatic impact is in the biodegradable polymer field. One of the most widely studied polymers in this family is poly-P-hydroxybutyrate (PHB) (64). A related member of the poly-P-hydroxyalkanoate (PHA) family commercialized by Imperial Chemical Industries (ICI), which later became Zeneca Bio Products,... 

While PHB and PHV are not considered true plastics, another biodegradable polymer polycaprolactone (PCL) is a plastic material because its monomer e-caprolactone is obtained on an industrial scale from petrochemical products (cyclohexanone and peroxyacetic acid). This synthetic plastic with its low melting point is easily extrudable and applications in the packaging area are envisioned. 

Biodegradable polymers can make a positive contribution to the conservation of the world s natural resources and protection of the environment. However, their market potential will only be fulfilled if the required framework conditions are put in place to ensure the necessary investment in technology and production capacity. Framework conditions refer to the development of industry standards and regulatory systems, certification and certification systems that are designed to encourage biodegradable polymer market development. 

The biodegradable polymers industry is also slowly receiving more political support to bolster market development. 

Wilkinson Industries Inc. became the first US company to manufacture thermoformed food containers and trays made from biodegradable polymers. The NaturesPLAstic product range is based on NatureWorks PLA polymers. 

Meanwhile, Fujitsu and Toray Industries have developed the first large-scale notebook computer housing based on polylactic acid biodegradable polymers. The housing is moulded of a specially developed PLA/polycarbonate blend that provide the required heat and flame resistance. 

PLA is the most commonly used biodegradable polymer found in fibre form. PLA fibre properties compare favourably with both PET and rayon fibres. Potential PLA fibre applications include apparel, bedding, carpet, furnishings, personal care, nonwovens and industrial textiles. 

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